A variety of techniques are available for recognizing what kind of object is being captured in an image. For instance, the technology for detecting a person's face from an image is quite common, as illustrated in Patent Document 1. This kind of recognition technique relies on creating a classifier beforehand on the basis of multiple images of the object to be recognized and then using the classifier during the recognition process.
Until now, however, the object to be recognized was somewhat limited because image capture was performed often manually and the object captured was often a person or scenery. The recent popularity of computer vision has increased the demand for the ability to recognize a larger variety of objects.